The burial ground of two kings and a queen is now a calm city park in the middle of bustling Seoul.

The world's longest bridge fountain has hundreds of nozzles that create a beautiful, illuminated spectacle.

About as hidden as can be, this specialty coffee shop is wedged between multi-story buildings at the end of a dark, skinny alleyway in Seoul.

A mysterious concrete hand reaches out from between the stones of Uniwersytecki bridge.

The gardens and chambers of this Moorish citadel conjure memories of the Alhambra.

There was a top secret plan during World War II to seal a group of soldiers inside the rock.

Single runway interrupted by a busy road that cuts across its middle.

Turntable anonymously received orphans, alms, and groceries.

Saint Borromeo often prayed in this austere crypt during the 16th century.

Third time's a charm, or in this case, two testicles are.

A brutalist gem towering over the heart of Milan.

Da Vinci's equestrian statue, 500 years in the making.

The mark of the Devil's horns on a marble column in Milan.

This grisly effigy displays an early Christian martyr who was skinned alive and beheaded.

Milan's duomo is covered in beautiful carving including a curious "dinosaur-like" beast.

An ossuary built in 1210 to collect bones from the Ospedale Maggiore of Milan.

A massive line that stretches across the floor of Bologna’s largest church was created by a 17th-century scientist to measure the movements of the Sun.

A large statue of Pope Gregory XIII in Bologna was disguised as Saint Petronius to avoid destruction.

Time has been frozen at this station since the bombing in 1980—or so it was believed.

Stuck in the arcade of Casa Isolani are three arrows of mysterious origins.

A striking memorial recalls thousands of Bolognese men and women killed fighting fascists in World War II.

This building features dozens of faces along its facade, although one is a bit chilling.

A diverse collection of wax, bone, papier-maché and mummified relics.

Legend has it this fountain built to symbolize the Pope’s power hides a strange secret concerning Neptune's manliness.